<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
</head>

<body>
    <script>
        // 1. 封装函数, 名字为sum
        // 2. 功能: 根据传入的两个数,求和并且返回求和的结果（函数必须有return返回值）
        let num1 = +prompt(`请输入第一个数`)
        let num2 = +prompt(`请输入第二个数`)
        let sum = 0

        function getSum(a, b) {
            sum = a + b
            return sum
        }
        let res = getSum(num1, num2)
        console.log(res);
    </script>
</body>

</html>